also is it possible that for some reason its hitting the first $uri or $uri/ in try_files instead of the last redirect?
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bryan_ruizJun 15 '13 at 15:28

I would agree that the try_files looks suspicious. Please understand that instead of throwing a 404, try_files will force the use of its last argument if it exists. So, it sounds like your setup is 404'ing, but you don't see it because it uses /index.php instead.
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earthmeLonJun 15 '13 at 20:22